Surface Marker Buoy and Air Share

[TSandM]

AquaExplorer, be aware that this is a skill which has to be learned, and there are hazards associated with it (getting wound up in the line and pulled to the surface among them -- where is that thread of Rick Inman's, anyway?) It's a good idea to have someone coach you through it the first few times (and you need good midwater buoyancy control, too). If you're interested in learning to do this, you might consider a PM to DIR-Atlanta here on ScubaBoard. I'm sure that would give you some information on an instructor or mentor who would be willing to show you the "ropes" (sorry, couldn't resist .

 

[DaleC]

Because in parts of the world you MUST carry and use a DSMB. Boats do not moor, sea surface conditions are rough, visibility is often low with rain, there are strong winds and strong currents working in different directions. You NEED an early bag to stand a chance of getting recovered. Why are we diving in those conditions? Because they're normal for some countries!

I'm pretty aware of what a SMB is and what it's used for. I just don't agree that deploying it while air sharing and ascending is a good thing to encourage. If someone stops, deploys, and then ascends, ok. That's not how I read the first post though.

Still waiting for the OP to define what "while ascending" means to them.

Is it really true though that in some places in the world operators are taking OW divers out for drift dives wherein, even though there is known current, if the diver doesn't immediately shoot a bag on the fly while ascending they risk being lost at sea? That there's no search plan for drifting divers. And if so, do the OW divers know how close to suicide they are cutting it?

I just find it hard to believe that non technical divers would put themselves in such a compromising position that they couldn't stop, shoot and ascend. Of course, with the crystal clear, calm waters that I dive in I might not be aware of difficult diving conditions.

My concern, as this is being discussed in basic scuba, is that new divers like AquaExplorer reading this thread will think, Hey I have to practice that! I am aware that some people responding in the affirmative have thousands of dives and/or are very experienced instructors or technical divers. That probably has some bearing on the answer.

 

[Troutmaster]

Dale,
I am picking up what you are laying down. You think it is too much task loading to be on ascent and shooting a bag instead of shooting the bag and THEN ascending.

It is like trying to shoot a gun from horseback. Pretty tough if the horse is going full speed. If you stop the horse for a second and make the shot, you have a much better chance of hitting what you are aiming at.

I agree that slowing down is the way to go. Share the air. Shoot the bag. Make the ascent. 3 separate steps. There is no need to be shooting the bag "on the fly" and it sounds like good way to have a runaway ascent.

I agree that this is getting past a "basic" scuba skill set, but if the diving you are doing requires you to be able to shoot a bag, then you better be able to do it while sharing air. In my opinion, this is one more argument for the use of a 7ft hose, but that is a whole other discussion.

As far as those advocating towing a bouy during the entire dive that is not for me. I have done it and it is a PITA. I would MUCH rather enjoy my dive and shoot the bag when I need it. I am sure there are some situations that require the towed marker but that would not be my first choice.

So lets all do it like Dale said. It is the old "Slow is Smooth, and Smooth is Fast" way of getting things done, and I like it.

 

[sambolino44]

I'm the buddy of the OP, and let me speak on her behalf. The last several posts have all been about a major misunderstanding; she never meant shooting a bag while simultaneously donating air and ascending. Each of the three things, sharing air, shooting the bag, ascending, would be done consecutively. Nevertheless, we've found that ascending while sharing air and also tending the line of your SMB (whether you've dropped the spool as Lynne suggests, or are reeling it in) is difficult to say the least. Whether this is a "basic skill" or advanced is relevant only to the point of did she put her post in the correct forum or not; the question remains: do you practice this or not.

Remember, this is also in the context of our local PNW diving, which means drysuits, current, and low viz, often at night. We shoot the bag not only to warn boats of our pending ascent, but also to provide a visual reference for our safety stop. I've posted elsewhere recently about our continuing efforts to improve our skill at hovering at 15' with no visual reference.

Another thing we have to consider is that, at least for me, I have to remain at least somewhat horizontal; if I go completely vertical all the air burps out my neck seal and I lose buoyancy. I've decided to add another drill to our skills dives; seeing what it's like if I go vertical, lose buoyancy from my suit, and have to switch to using my wing for buoyancy. Probably a good skill to have in my bag in case my suit rips anyway.

Thanks from both of us for all the thoughtful comments; it's been great to read all the different perspectives.

As for us, we do practice these, and have recently decided to scale back a bit and as someone suggested get really good a each skill individually before we start combining them.

I'm convinced, though, that for the diving we do it would be a good thing to be proficient at all three. We used to practice skills more often, about every other or every third or fourth dive. Lately we've been less rigid. I think we should get back on a more disciplined schedule until we're comfortable with the skills that we think should be basic for the conditions we dive in regularly.

 

[String]

I'm pretty aware of what a SMB is and what it's used for. I just don't agree that deploying it while air sharing and ascending is a good thing to encourage. If someone stops, deploys, and then ascends, ok. That's not how I read the first post though.

I took it to mean sort out the emergency (establish sharing), then shoot bag, then ascend up line. It only involves stopping for 30 seconds or so.

Is it really true though that in some places in the world operators are taking OW divers out for drift dives wherein, even though there is known current, if the diver doesn't immediately shoot a bag on the fly while ascending they risk being lost at sea?

Many places. Most charter boats in the UK wont allow you on board without your own DSMB and the ability to use it regardless of diver grade. They're 100% essential for all dives in some areas. If the local sea conditions dictate that its the way things are done. It's also why the british based agencies have deployment as a core part of the courses.

That there's no search plan for drifting divers. And if so, do the OW divers know how close to suicide they are cutting it?

Of course theres a plan but the plan doesnt always work. With winds sometimes 20-30kts in one direction and a swirling current 5-6kts in another people get spread out, fast.
Searches take time and although the computer software and services are good are not always successful. Add that to exposure issues if they're dull enough to wear a wetsuit and its simply not safe.

My concern, as this is being discussed in basic scuba, is that new divers like AquaExplorer reading this thread will think, Hey I have to practice that! I am aware that some people responding in the affirmative have thousands of dives and/or are very experienced instructors or technical divers. That probably has some bearing on the answer.

Shooting a DSMB is basic scuba. Its taught as entry level in places. Its REQUIRED to dive in some places. Its also not difficult.

 

[DevonDiver]

Shooting a DSMB is basic scuba. Its taught as entry level in places. Its REQUIRED to dive in some places. Its also not difficult.

I think any diver should be able to apply their emergency drills under any circumstances and in conjunction with any other pre-planned aspect of the dive (including DSMB deployment).

It would be good problem solving to avoid concurrent over-tasking and deploy the DSMB prior to beginning ascent, whether or not you were sharing your air.

However, what about a scenario where you have begun ascent and planned to deploy your DSMB from shallow? Midway through the ascent, your buddy signals OOA?

Basically, the best advice is to think about your dive plan. It should reflect the way you practise your skills...and vice versa.

Think through "what if" scenarios and see if you already have the answer and have practiced the skill enough for it to be 'instinct'. Don't assume that you can cope if the circumstances and tasks change.

 

[MXGratefulDiver]

Another thing we have to consider is that, at least for me, I have to remain at least somewhat horizontal; if I go completely vertical all the air burps out my neck seal and I lose buoyancy. I've decided to add another drill to our skills dives; seeing what it's like if I go vertical, lose buoyancy from my suit, and have to switch to using my wing for buoyancy. Probably a good skill to have in my bag in case my suit rips anyway.

It's a good skill to have, Sam ... using your BCD for buoyancy control is also a good habit to get into.

I cannot, for the life of me, understand why instructors and drysuit manufacturers tell people to use their drysuit for buoyancy control. That's what your BCD is for. Drysuits should only contain enough air to provide loft for your undergarment. That way the excess won't be burping out your neck seal if you should have to orient yourself vertically.

David Chamberlin explains this in his article on dynamic instability ...

... Bob (Grateful Diver)

 

[DaleC]

Thanks for the feedback Sam, that clarifies things.
And, of course, I think practicing those skills are a great idea.

 

[Soakedlontra]

Here I am the OP!

Thanks Sambolino for writing on my behalf! I did not realized that since I posted my last post the discussion had developed 'homozygously' (I have just found it on the dictionary and I don't know what it means...it sounds good, though) in such a short time.

Whether this thread should not be in the 'basic scuba discussions' or not is up to a moderator to decide. However moving this discussion to the 'advanced scuba discussions' does not make sense to me. I posted here because I did not think that the deployment of a SMB is considered an advanced scuba skill. Certainly when it is combined with air share things become more complicated.

I have been carrying a SMB since I have got certified two years ago and occasionally been practicing its deployment and ,separately, air share. So why another OW diver should not do the same? As Lynne mentioned it is important to do it with a buddy who is more experienced or an instructor in a safe environment (a dive site where current and surf is not an issue, there is a point of reference, beside the line of the SMB, and has a relatively flat sandy bottom at 25/30 fsw.).

Dale what I mean is: if my buddy is in a out of air situation at depth and the environmental conditions requires the deployment of a SMB I will share air, then deploy the surface marker buoy and then begin to ascend. I did not mean to do everything simultaneously!:shocked2: However, as Devon Diver mentioned, unfortunately there are so many different scenarios in scubadiving that in some occasions I may have to be able to do those skills almost simultaneously.

Now to complicate things even more I have just realized that with our SMB (a 6 ft tall DAN SMB) doing air share and deploying that kind of sausage is more problematic because we usually inflate it with our primary regulators. So when we share air we donate our regulator that's attached to a 5ft long hose and breath from a regulator attached to a necklace that's located around our necks. So if I have to donate my primary regulator to the AOA buddy I don't think it would be very practical to mess with the regulator on my necklace to inflate the SMB.

We probably have to change our strategy and inflate the SMB with the inflator hose of our BC instead...something that I have never practiced... Another alternative would be to get rid of that big SMB and buy a smaller one that we could inflate orally. Well Sam bought the 6 ft SMB because it was recommended by DAN. Apparently after a study, the DAN folks decided that a big SMB was more visible than a smaller one...Of all the other divers I have seen so far we are the only ones who carry such a big SMB.

Is there a third option?

At that point, there was a further complication. The trainee divemaster approached me and showed me the display on their dive computer... showing me the universal sign for 'confused'

At a glance... their computer had entered deco mode. They had never seen that before and thought it was "a computer display glitch or something". In the end, the entire group did an extended safety stop of 8 minutes, whilst the DMT decompressed. Because I had a diver still low on air, the DMT concerned got to practice air-sharing with them... I didn't want to send the group up without me, as there were numerous boats on the surface (they probably wouldn't recognize our boat), surface current, boat movement, swell....and I already believed the group was not 'switched on' and aware of risks. I wanted to keep control for their safety.

Interesting that you wrote this DevonDiver. It makes me think of another 'heated' thread that I have started a while ago:

http://www.scubaboard.com/forums/computers-gauges-watches-analyzers/346334-off-wall-question.html

 

[Blackwood]

whether deco for a 280 dive, or just slow ascent after a 60 foot dive for around an hour, why would you not just do a simple circling ascent?

Remind me why I want to swim in circles rather than relax...